Latch



w. U. vlNToN April 4, 1950 LATCH A 3 Sheets-Sheet 1 Filed Dec. 13, 1945IIIIIIIII lllllllllll INVENTOR. 1MM/w a mwa/v W. U. VINTON Apri14, 195oLATCH 3 Sheets-Sheet 2 Filed Dec. 15, 1945' Afro/@MM Aprl 4, 195o Filedvee, '15, 1945 w. U. vlNToN 1N VEN TOR.

Patented Apr. 4, 1950 LATCH William U. Vinton, Manitowoc, Wis., assignorto Manitowoc Shipbuilding Company, Manitowoc,

Wis.

.Application December 13, 1945, Serial N0. 634,774

1 Claim. l

This invention relates to latches for cabinets and is particularlydirected to a latch for a low temperature cabinet.

In latches for cabinets as heretofore constructed, it has frequentlyhappened that that latch is so constructed that there is an unbalancedforce which is transmitted to the door and tends to either shift ordistort the door. Also in certain types of latches there is aconsiderable amount of unnecessary friction which materially hampers thefree operation of the latch. In addition to this, usually the latchesare so constructed that they do not draw the door inward ly to anyappreciable extent but merely latch the door after the door has beenforced to the innermost position that it is to occupy. When it isconsidered that these doors are so arranged that they compress yieldinggaskets or seals around the margins olf the doors, it is apparent thatit is highly desirable to insure adequate compression of the gaskets soas t prevent entrance of air around the margins of the door.

This invention is designed to overcome the above noted defects andobjects of this invention are to provide a novel form of latch which isparticularly suitable for low temperature cabinets where the doorcompresses a yielding gasket and thus provides a complete sealing effectall the way around the door and which is arranged to provide a balancedthrust or force from opposite directions so that there is no resultantforce transmitted to the door which might tend to distort or causeshifting of the door.

Further objects are to provide a latch construc tion for a lowtemperature cabinet having a yielding gasket, which latch constructionis so made that it has a very powerful inward pull to thus insureadequate compression of the sealing gasket and which is so made that itmay be operated with a minimum of eiort, the eiective operating parts ofthe latch being arranged symmetrically about the catch so that theypress in diametrically opposite directions and thus produce a balancingof the forces as heretofore mentioned.

Further objects are'to Iprovide a latch construction in which a largenumber of the parts are formed from simple stampings, which is so. madethat it may be very readily assembled and may be easily applied to thedoor, and `which requires only a very small opening in the rear part ofthe door, and which is arranged to coact with the door and with theadjacent portions of the cabinet to prevent entrance of air through anyportion of the latch.

An embodiment of the invention is shown in the accompanying drawings, inwhich:

Figure 1 is a fragmentary view with parts broken away and in sectionshowing the latch in its locked or latched position.

Figure 2 is a view corresponding approximately to Figure 1 and showingthe latch in released position.

Figure 3 is a view looking. at the edge of the door with parts brokenaway and in section.

Figure 4 is a sectional view on the line 4-4 of Figure 1.

Figure 5 is a top view of the latch detached from the door.

Figure 6 is a sectional view on the line 6-6 of Figure l. y

Figure '7 is a sectional view on the line 'l-'l of Figure 1.

Referring to the drawings, it will be seen that a low temperaturecabinetdoor has been indicated by the reference character l and that the bodyportion of the low temperature cabinet has been indicated by thereference character 2. The door indicated generally bythe referencecharacter l has an outer wall 3 and an inner wall 4 and has the spacetherebetween filled with an insulating material 5. At the point wherethe latch is positioned on the door a notch or rectanguiar opening isformed and is provided with an inner wall B, see Figure 4, and upper andlower walls '1' and 8, see Figure 1. The rear wall of the door extendsto approximately the marginal edge of the door but is separatedtherefrom'by means of a narrow marginal strip 'l which forms a part ofthe rear wall of the door. A yielding gasket indicated generally at 9 iscarried either by the door or by the body of the cabinet. As shown inFigure 4, this sealing gasket is carried by the door.

Any suitable type of sealing gasket could vbe employed with the form oflatch disclosed by this invention provided there is a certain degree ofyield or compressibility of the gasket as will appear hereinafter.

The latch comprises an outer casting or member Ill. The casting Ill isprovided with a flanged portion I l which is curved and which iitsagainst the curved front wall 3 of the door, see Figures l, 2, and l. Itis detachably secured to a metal vboxlike member or housing i 2 by meansci upper and lower screws i3.' These screws pass through the upper andlower walls of the box-like member l2 and into upper and lower angleirons or fastening clips I4 which latter are of relatively heavy stock.These clips have angularly turned ends l5 which are positioned againstthe rear marginal portion 1 of the rear wall and are detachably securedthereto by means of upper and lower screws I6. The casting l is providedwith an outwardly projecting portion I1 which is rectangular inhorizontal cross-section and curved or arched in vertical cross-sectionas may be seen by a comparison of Figures 4 and 2. The portion I1 isprovided with a slot I8 through which a handle I9 projects. The handleI9 is pivoted on a pin 2D carried by outwardly turned ears 22 formedintegral with a plate 23, the plate being detachably secured to theouter wall of the housing or boxlike member I2 by means of screws 24'.The ears 22 are provided with inwardly turned lips 24, see Figures 1, 2,and 6, which act as stops for the lower face 25 of the body portion ofthe handle I3. The upper face of the body portion of the handle isindicated by the reference character 26 and is adapted to coact with therounded end of a plunger 21 to press the plunger inwardly when thehandle is rocked in a counter-clockwise direction as viewed in Figure 2.The plunger 21 is provided with an inner head 28 and is prevented fromtilting by the relatively thick apertured member 29 which is welded tothe plate 23 and which provides an extended sliding bearing surface forslidably receiving the plunger 21.

A pair of arms or small levers 30 are formed of identical stampings andmay be channelshaped as indicated. The arms are pivoted on pins 3icarried by the box-like housing I2 and are provided with rollers 32 attheir free or outer ends, the rollers being positioned within thechannels of the arms 36, as shown clearly in Figures 1, 2, and 4. Thelevers 33 and consequently the rollers 32 are urged inwardly 4by meansof relatively heavy compression springs 33 which are seated at one endaround lugs 34 formed rigidly with the levers 36 and at their other endsin apertures 35 formed in the brackets I4. The inward motion of therollers 32 and of the levers 30 is limited by the engagement with theflange or head 2B of the plunger 21 when such head bears against therear wall of the housing or box-like member I2 as shown in Figure 1.

From an examination of Figures l and 2, it will be seen that the levers3i) constitute bell crank levers. Their long arms carry the rollers 32and their short arms bear against the head 28 of the plunger 21.Consequently, it is clear that the springs 33 tend to rock the leversabout their pivots 3l and to force the plunger 21 to the right, asviewed in Figures l and 2, and consequently tend to rock the handle downinto its normal position shown in Figure 1. However, when the handle ispulled outwardly so that it rocks in a counter-clockwise ldirection fromthe position shown in Figure l to that shown in Figure 2, it will beseen that the plunger 21 is moved inwardly to the left. This causesoutward rocking motion of the levers 36 against the action of thesprings 33 and. detaches the rollers 32 from the catch 36 hereinafterdescribed.

The catch 36 is made with an arrow head at its end as shown very clearlyin Figures 1 and 2. If desired, the inner surface of the rear portion ofthe arrow head may be rounded as indicated by the reference character 31so as to conform approximately to the contour of the rollers. The arrowhead is connected with a threaded stem portion 38 of the catch by meansof a narrow fiattened neck 39. It is to be noted from reference toFigure 2 that the rear wall, namely the portion 1 of the door, isprovided with an aperture 40 slightly bigger than the arrow head 36 ofthe catch so as to allow the catch to enter the corresponding part ofthe door when the door is closed.

The catch is made adjustable by providing the threaded stem 33,hereinbefore described. This stem is screwed into a reinforcing ornut-like member 4I located inwardly of a reinforcing bracket 42 and thebracket and nut-like portion are secured within the body portion 2 ofthe cabinet. The threaded stem 38 of the catch is provided with aflattened portion or cut-away portion 43. A locking plate or fitting 44,see Figure 7, is passed over the stem 38 and is contoured to t the stemwith its flattened portion 43 and to prevent rotation of the stem undernormal conditions. This fitting 44 is detachably secured to the bodyportion 2 of the cabinet by means of screws 45. This construction,therefore, allows adjustment of the latch inwardly or outwardly tocompensate for wear on the gasket 9 due to extended use of the lowtemperature cabinet. For instance, the screws 45 may be removed and thelatch given a half turn, this adjustment of the catch being made whilethe door is in open position. Thereafterv the screws 45 are replaced andthe catch is prevented from further rotation. The catch may thus bescrewed in or out to provide the exact adjustment desired to secureadequate and accurately adjusted compression of the sealing gasket 3,see Figure 4.

The door, in locked position, is shown in Figure 1. When the handle I9is rotated in a counterclockwise direction the rollers 32 are movedoutwardly to the `position shown in Figure 2, out of locking engagementbehind the arrow head 36 of the catch and consequently the door may bepulled open by continued pulling of the handle. When the door is closed,the arrow head 36 of the catch passes between the rollers 32 and forcesthe rollers apart as the tapered arrow head passes therebetween. Thiscompresses the springs 33. However, as soon as the center of rotation ofthe rollers 32 passes `behind the ears of the arrow head 36, the rollersare forced inwardly with a heavy pressure by means of the springs 33towards the position shown in Figure 1 and thus an extremely heavyinward thrust is imparted to the door. This draws the door tightlyclosed and compresses the gasket 3. The position shown in Figure 2 isthat where the center of rotation of the rollers is just passing theextreme ends of the rear portions of the arrow head 36 of the catch.From this position to that shown in Figure l, it will be seen that thedoor has been moved inwardly a material distance, thus adequately andpowerfully compressing the gasket 9 and securing a perfect seal withoutany eiort on the part of the operator.

It is apparent that a very small opening is required in the rear fall ofthe door for the passage therethrough of the catch portion of the latch.The curved portion I l of the main casting Ill of the latch constitutes,in eiect, an escutchecn and provides a finish for the door. In additionto this, it covers the front opening or rectangular notch formed in thedoor.

It is to be noted particularly that the latch is formed of very simpleparts and is so arranged that the springs 33 produce a balanced thrustfrom opposite directions and consequently no resultant force tending todistort or shift the door is imparted to the door. There is thus notendency due to the latch towards causing the door to sag or becomeshifted or distorted. In

addition to this, actual tests have shown that a latch constructed inaccordance with the disclosure of. this invention is easily capable ofproducing as much as a 15G-pound inward pull on the door though thisfigure is not to be taken as a limiting value but merely as anillustration of the result of one design of the latch. Obviously thelatch could be designed to provide any desired thrust tending to closethe door. Also itk It is to be noted that many of the parts of the.

latch are duplicates and are of very simple construction and may beformed of stampings. The levers 30 are duplicates and are easily formedfrom stampings. The rollers 32 as well'as the springs 33 and the cli-psI4 are also duplicates.

A further feature ofmaterial importance is the ease with which the latchmay be applied to the door or removed therefrom for inspection orrepair. Only two screws I6, see Figure 2, need be removed and thereafterthe latch may be lifted directly outwardly from'the door. The otherparts of the latch may be readily disassembled and reassembled asrequired.

It will be seen, therefore, that a novel form of latch has'been providedwhich is particularly suitable for a low temperature cabinet and whichexerts an inward powerful closing force on the door and is easy tooperate and is of a simple and readily made construction.

6 Although this invention has been described in considerable detail, itis to be understood that such description is intended as illustrativerather than limiting, as the invention may be variously embodied andisfto be interpreted as claimed.

I claim:

A latch construction for a cabinet having a' body portion and a door,said latch construction comprising a catch carried by said body portionand projecting outwardly therefrom and terminating in an arrow headshaped end, and a latch construction comprising a housing, a pair ofpivoted levers mounted within said housing and provided wtih rollers attheir free ends adapted to engage inwardly of the arrow head end of saidcatch, the axes of said rollers being parallel to the axes about whichsaid levers pivot, spring means urging said rollers towards each other,

said rollers coacting with the arrow head shaped end of said catch todraw said door inwardly, a plunger adapted to rock said levers and movesaid rollers apart to disengage said rollers from saidl catch, saidplunger being guided and passing through said housing, yand a handlepivotally supported from said housing and having a portion arranged tobear against and project said plunger inwardly when said handle isrocked.

WILLIAM U. VINTON.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,191,679 Dziegielewski July18,1916 2,096,980 Schjolin Oct. 26, 1937 2,165,896 King July 11, 19392,259,136 Hogg Oct. 14, 1941

